The electrical activity of the muscles in the heart directs the overall activity of the heart. Many heart malfunctions, particularly arrhythmias, are evidenced by or caused by electrical activity that is not suitable for the heart's normal functioning. The electrical leads described herein are useful in the detection of the heart's electrical activities and in its treatment by stimulation, ablation and defibrillation.
Electrical leads having electrode regions have been used in the medical field for applications such as those referred to above.
Traditionally, the electrodes have been made from machined metal or coiled wire components which, while having the requisite electrical conductivity, fail to provide the desired degree of flexibility required in a medical application.
Although the use of metal coated or metal filled polymers as medical electrodes has been considered, the amount of metal required to obtain a suitable level of conductivity renders the resultant lead stiff and not particularly suitable for implantation into a patient.